Method exchangeCodeForTokens

src/node/services/codexOauthService.ts:424–481

(input: {
    code: string;
    redirectUri: string;
    codeVerifier: string;
  })

  }

  private async exchangeCodeForTokens(input: {
    code: string;
    redirectUri: string;
    codeVerifier: string;
  }): Promise<Result<CodexOauthAuth, string>> {
    try {
      const response = await fetch(CODEX_OAUTH_TOKEN_URL, {
        method: "POST",
        headers: { "Content-Type": "application/x-www-form-urlencoded" },
        body: buildCodexTokenExchangeBody({
          code: input.code,
          redirectUri: input.redirectUri,
          codeVerifier: input.codeVerifier,
        }),
      });

      if (!response.ok) {
        const errorText = await response.text().catch(() => "");
        const prefix = `Codex OAuth exchange failed (${response.status})`;
        return Err(errorText ? `${prefix}: ${errorText}` : prefix);
      }

      const json = (await response.json()) as unknown;
      if (!isPlainObject(json)) {
        return Err("Codex OAuth exchange returned an invalid JSON payload");
      }

      const accessToken = typeof json.access_token === "string" ? json.access_token : null;
      const refreshToken = typeof json.refresh_token === "string" ? json.refresh_token : null;
      const expiresIn = parseOptionalNumber(json.expires_in);
      const idToken = typeof json.id_token === "string" ? json.id_token : undefined;

      if (!accessToken) {
        return Err("Codex OAuth exchange response missing access_token");
      }

      if (!refreshToken) {
        return Err("Codex OAuth exchange response missing refresh_token");
      }

      if (expiresIn === null) {
        return Err("Codex OAuth exchange response missing expires_in");
      }

      const accountId = extractAccountIdFromTokens({ accessToken, idToken }) ?? undefined;

      return Ok({
        type: "oauth",
        access: accessToken,
        refresh: refreshToken,
        expires: Date.now() + Math.max(0, Math.floor(expiresIn * 1000)),
        accountId,
      });
    } catch (error) {
      const message = getErrorMessage(error);
      return Err(`Codex OAuth exchange failed: ${message}`);
    }
  }